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Reversible dioxygen binding on asymmetric dinuclear rhodium centres
Takayuki Nakajima1, Miyuki Sakamoto, Sachi Kurai
1Department of Chemistry, Faculty of Science, Nara Women's University, Kitauoya-nishi-machi, Nara 630-8506, Japan. t.nakajima@cc.nara-wu.ac.jp
Chemical Communications (Cambridge, England)
|April 11, 2013
Summary
Dinuclear rhodium complexes with a tetraphosphine ligand reversibly bind molecular oxygen. This forms asymmetric dirhodium peroxo complexes stabilized by a rhodium-rhodium dative bond, showcasing novel oxygen coordination chemistry.
Area of Science:
- Coordination Chemistry
- Organometallic Chemistry
- Materials Science
Background:
- Dinuclear rhodium complexes are of interest due to their unique electronic structures and catalytic potential.
- The development of ligands that facilitate reversible small molecule binding is crucial for catalysis and sensing applications.
- Understanding the interaction of metal complexes with molecular oxygen is fundamental in inorganic chemistry.
Purpose of the Study:
- To synthesize and characterize electron-deficient dinuclear rhodium complexes.
- To investigate the reversible binding of molecular oxygen to these rhodium complexes.
- To elucidate the structure and bonding of the resulting peroxo complexes.
Main Methods:
- Synthesis of dinuclear rhodium complexes featuring the linear tetraphosphine ligand dpmppp.
- Exposure of the rhodium complexes to molecular oxygen under controlled conditions.
- Characterization of the resulting peroxo complexes using spectroscopic and structural techniques (implied).
Main Results:
- Successfully synthesized electron-deficient dinuclear rhodium complexes, denoted as [Rh2Cl2(μ-dpmppp)(RNC)] (1).
- Demonstrated reversible binding of molecular oxygen to complexes (1).
- Formed asymmetric dirhodium η(2)-peroxo complexes, [Rh2Cl2(O2)(μ-dpmppp)(RNC)] (2), stabilized by a Rh→Rh dative bond.
Conclusions:
- Electron-deficient dinuclear rhodium complexes can reversibly coordinate molecular oxygen.
- The formation of asymmetric peroxo species is facilitated by the ligand framework and a Rh→Rh dative bond.
- These findings contribute to the understanding of oxygen activation by dinuclear metal centers.
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